Fiber yarn and cloth using the same

ABSTRACT

In view of the demand to replace wood pulp to preserve forests which is brought about by the recent trend to preserve natural resources from the terrestrial warming or the environmental pollution, this disclosure provides a yarn using cellulose-based filament yarn made from bamboo. This is achieved by a fiber yarn which is a yarn containing a filament of cellulose-based fiber made from a bamboo having a thickness of about 10 to about 600 dtex and number of twist of 0 to about 3,000 T/M.

TECHNICAL FIELD

This disclosure relates to a cellulose-based fiber yarn made from abamboo and a cloth using the same which constitutes a woven or knittedfabric or non-woven fabric.

BACKGROUND

Conventionally, as a starting material for cloth such as woven orknitted fabric or non-woven fabric, in natural fiber field, startingmaterials by cultivation or farming has been used. In the chemical fiberfield, it is mostly occupied by cellulose-based regenerated fiber inwhich natural starting material is used, semi-synthetic fiber,protein-based fiber and synthetic fiber in which coal or petroleum isused as starting material. However, recently CO₂ increase due tolumbering forests for producing fibers or the like, or environmentalpollution and terrestrial warming due to increase of coal- andpetroleum-based industrial waste have become big problems.

For solving these problems and for terrestrial environmentalpreservation, research and development proceeded to change thosestarting materials to biomass resources (resources other thanpetroleum), and not only commercialization of polylactic acid fiber, PLA(polylactic acid) made from starches of corn or sweet potato, but alsoother developments based on bio-technology have been made rapidly. Inaddition, to produce fibers by cultivation, a technology for extractingfiber by mechanical methods such as slitting and splitting from bamboo,kenaf or month peach was developed and about to be commercialized.However, in this technique, although staple-fiber can be made, it isimpossible to make continuation filament. On the other hand, although itis being tried to make a fiber from lees of soybean for food, it is atechnique for making a staple fiber and it has not yet succeeded to makea continuous filament. Also, a fiber yarn is proposed in which Indianbamboo is spun as a cellulose rayon fiber to make a staple fiber, and itis spun to make a yarn, and, by controlling thickness and number oftwists of the fiber yarn, tenseness, resilience and recovery fromcreases are more improved compared to woven or knitted fabric ofconventional cellulose rayon fiber. JP-A-2001-115347. However, it hasnot been tried to take out cellulose from bamboo and make it intofilament for fabrics such as woven, knitted and nonwoven fabrics.

Although, there is a publication describing about obtaining a textile bymixing a polyester type synthetic fiber to a staple fiber yarn made frombamboo and it is effective for stretchability and touch, but a filamentyarn is not indicated. JP-A-2003-113554.

This disclosure makes it possible to industrially produce acellulose-based filament by removing impurities such as resin componentand ash component to thereby take out the cellulose component with agood purity. And, using the filament made by this new technology, thisdisclosure makes it possible to make a fabric made thereof such as wovenor knitted fabric or nonwoven fabric.

SUMMARY

This disclosure replaces wood pulp and provides a yarn or acellulose-based filament made from bamboo, or a fabric made thereof.When a bamboo or the like is used as a starting material, there is noenvironmental load, since the growth of bamboo is fast and its oxygenproduction and CO₂ absorption effect is large and, even if CO₂ isproduced in the fiber production and in the incineration of garmentwaste, the CO₂ produced is equivalent to that absorbed and fixed fromthe air during its growth. Furthermore, like conventional wood pulp, itis possible to maintain the high moisture absorption/desorptioncharacteristics of cellulose fiber, an excellent luster, a cold touchbrought about by the absorption/desorption characteristics and, inaddition, a dry touch brought about by the quality of bamboo cellulosedifferent from the conventional rayon made from wood or cotton linter asstarting materials. Moreover, by a composite design in combination withother fiber, it is possible to provide a fabric which has wearingimpressions such as sweat absorption/quick drying property,stretchability, etc., or generation of negative ions as a healingeffect, and further, increase proofing property, pleat retentionproperty and the capability of home laundry, especially, water systemlaundry. In addition, it is also possible to provide a sanitary woven,knitted or nonwoven fabric comprising the cellulose-based fiber and asynthetic fiber having an anti-bacterial characteristic or a system germcharacteristic.

Selected aspects of this disclosure include:

(1) A fiber yarn which is a yarn containing a filament ofcellulose-based fiber made from a bamboo whose thickness is 10 to 600dtex and a number of twist is 0 to 3,000 T/M.

(2) A fiber yarn according to (1), characterized in that an α-cellulosecomponent content in said filament being 80% by weight or more.

(3) A fiber yarn according to (1) or (2), characterized in that a totalcontent of α- and β-cellulose component in said filament being 90% byweight or more.

(4) A fiber yarn according to any one of (1) to (3), characterized inthat said filament is manufactured by a viscose rayon continuousspinning method.

(5) A fiber yarn according to any one of (1) to (4), characterized inthat said fiber yarn contains at least 20% by weight of said filamentand other fiber is at least one selected from the group consisting of anatural fiber, a regenerated fiber, a semi-synthetic fiber and asynthetic fiber.

(6) A fiber yarn according to any one of (1) to (5), characterized inthat said cellulose-based fiber is made from a biomass resource as rawmaterial.

(7) A fiber yarn according to any one of (1) to (6), characterized inthat said filament and said other fiber are made composite by a methodselected from doubling and twisting, intersection twist, covering,filament mixing, false twisting and spinning intersection twist.

(8) A cloth characterized in that it is a woven or knitted fabric or anonwoven fabric using the fiber yarn described in any one of (1) to (7).

DETAILED DESCRIPTION

By making woven or knitted fabric or nonwoven fabric with monofilamentyarn or multifilament yarn of a cellulose-based filament made from anatural or cultivated bamboo, filament in the filament yarn is in astraight condition and becomes rigid by twisting and therefore, comparedto a spun yarn of staple fiber made from a bamboo, it excels intenseness, resilience, or drapability of textile structure. Moreover,compared to textiles using rayon filament made from conventional woodpulp and cotton linter, the fabric has an excellent effect such that itexhibits a particular quality in dry touch, resilience and drapabilitybased on its basic quality. Furthermore, it is possible to providetextiles such as knitted, woven or nonwoven fabric in which a compositeyarn with other natural fiber, chemical fiber such as cellulose-based,synthetic fiber staple, spun yarn or filament. The textile has effectssuch that, when it is put on, there is no sweaty feel byabsorption/desorption; there is no tacky feeling by sweat absorption,there is no feeling of oppression by stretch following body motion, orthere is a healing effect by generation of negative ions, although it isnot easily realizable. Furthermore, it has increased proofing property,pleat retention property and capability of home laundry, especially,water laundry. In addition, it has an anti-bacterial characteristic or asystem germ characteristic. Moreover, in manufacture and disposal of thematerial for garments and garments goods, the fiber yarn can bedeveloped into a material for garments and garments goods which cansatisfy the demand that an environmental load can be lessened. From theapplication of wear near skin, such as underwear and dress shirts forcasual application or relatively outer wear such as woman's andgentleman's jacket, trousers, or jeans etc., it can be used preferably.Moreover, since it has these properties, it is preferably applicablealso as sports garments, work wear for the medical field, and caregarments. Further, it is applicable also as an interior application,such as an outer cloth for futon, a sheet, a curtain, and a cover sheetof chair.

The yarn containing the cellulose-based filament made from bamboo isused. What is necessary is to contain the cellulose-based filament madefrom bamboo and, of course, a filament consisting of 100% of thecellulose-based filament made from bamboo is included in the filament.It is preferable, for exhibiting the effect, that the cellulose-basedfilament made from bamboo is contained at 20% by weight or more in thebamboo containing filament yarn.

The cellulose-based filament made from a bamboo means, unlike thechemical fiber which uses wood pulp or cotton linter pulp as a rawmaterial, a filament made by making a pulp from a bamboo, refining thepulp to obtain cellulose, spinning the cellulose to obtain a fiber.Although it has not been known that a continuous filament can beindustrially obtained by using a bamboo as a raw material and bydissolving and spinning it, we made it possible by refining it in thestage of bamboo pulp.

So-called bamboo is also included in the bamboo. The classification ofbamboo and so-called bamboo is described in “knowledge of bamboo”:written by Hiroshi Muroi, the first edition published on May 20, 1977 byChiin Shoin.

Conventionally, most of 350 sorts of bamboo grown in China can be usedfor manufacturing pulp for paper, but second or third grade of jichiku,ouchiku or suichiku in Chinese name which are naturally grown orcultivated widely and abundantly around Sichuan of China can preferablybe used. These bamboos are cut down and their parts with especially highimpurity content such as stems, branches and leaves are removed, and aremade into chips by physical and mechanical action, and then they aremade into a pulp as a fiber manufacturing raw material.

The filament can be obtained with the conventional manufacturingtechnology for the chemical fiber. A regenerated fiber obtained by theviscose process or the cupro ammonium process, a purified cellulosefiber obtained by an organic solvent spinning method, a celluloseacetate semi-synthetic fiber, and a cellulose-based fiber obtained bythermal plasticization and melt spinning of cellulose are preferablyused. Here, regarding manufacture of the regenerated fiber by theviscose process, the conventional wet spinning method, in which aviscose spinning solution is made using alkali xanthate and carbondisulfide by using wood pulp or cotton linter pulp as a raw material,and the obtained spinning solution is spun into a sulfuric-acid bath tothereby obtain a fiber, is also applied.

In manufacture of the filament, it becomes possible to obtain amonofilament or multifilament with thin single fiber fineness by using abamboo for pulp, refining the pulp further, reducing the content of thecellulose of low molecular weight, pentosan, lignin, pitch and ash, andmaking the α-cellulose content of primary pulp (pulp made from bamboo asa raw material by the pulp process by chemical or mechanical method) to85% by weight or more. Regarding the pulp made from wood or cottonlinter for conventional cellulose-based fiber such as rayon, accordingto the description in the item of dissolved pulp for rayon from P179 ofthe Chemical Fiber Handbook (edited by Society of Fiber Science andTechnology, Japan and published by Maruzen Co., Ltd. on May 28, 1963),α-cellulose content is specified as 91.8% or more by JIS standard, andthe quality standard of the pulp for cuprammonium rayon is 96% or more.However, about the pulp made from a bamboo, the α-cellulose componentcontent of the industrially manufactured pulp which is used for fibermanufacture has not been publicly reported and is not clear.

The manufacture method of the cellulose-based fiber filament made frombamboo is explained hereunder.

When bamboo pulp for paper manufacture is used as a raw material withthe same process conditions as the case where wood pulp and a cottonlinter are used, fiber strength is low and satisfactory fiberperformance cannot be obtained, since the α-cellulose component contentof the bamboo fiber is low and the contents of β-cellulose, other lowmolecular weight celluloses, pitch and ash component are high.Accordingly, spinnability is not good, since the polymerization degreeand crystallinity may be low. Spinning filament was tried by selectingthe kind of bamboo, and using a pulp capable of manufacturing staplefiber in which the contents of low molecular weight celluloses, pitchand other impurities were decreased, but spinnability was bad due tofiber breakage at spinning and industrial production was impossible. Itwas found that the bamboo pulp can be spun into filament by increasingthe α-cellulose content to 87% by weight or more by selecting the kindof bamboo, improving conditions for manufacturing pulp and fiber, andrefining the material at the stage of pulp.

During our research, to compare the structure of the viscose rayonfilament made from bamboo pulp and the viscose rayon filament made fromconventional wood pulp or conventional cotton linter, thermogravimetricanalysis, component analysis by X-ray fluorescence, crystallinityevaluation with the crystal structure parameter by wide angle X-rayintensity distribution measurement, etc. were conducted. Since thecrystallinity of the bamboo rayon fiber is lower, it was presumed thatthere was a difference between cellulose components of the filaments,and that the difference brings about the difference of performances ofthe woven or knitted fabrics of bamboo fiber and of the fiber made fromconventional wood pulp or cotton linter. Therefore, we compared thecontent of α-, β-cellulose, other low molecular weight cellulose,residual pitch and others, and as a result, it became clear that theviscose rayon filament made from the bamboo cellulose has low content ofα-cellulose component compared with the filament made from wood or acotton linter cellulose, and there is a large content of γ-cellulose,other low-molecular-weight celluloses, impurities, etc. By thismeasuring method, it is believed that the reason for that the content ofthe α-cellulose component of the filament is low is because, in theviscose process in which a strong alkali and sulfur dioxide reacts, therelatively low molecular weight component in molecular distribution ofthe α-cellulose component is further decomposed into a lower molecularweight due to the chemical effect of the molecular weight adjustment inthe aging process and due to the use of the viscose spinning solution ofalkali xanthate. Because the content of β-cellulose component in bamboois high, it is believed to further decompose into low molecular weightand content of α- or β-cellulose decreases.

As such viscose wet spinning method, although there are centrifugal typespinning and continuous spinning methods, the continuous spinning methodcapable of making fiber thin by drawing is preferable because itsmolecular orientation is good to thereby improve fiber property, andexcellent in uniformity of dyeing. In addition, a centrifugal spinningmethod, so-called “cake winding” method is insufficient in drawingeffect because the distance of spinneret and pot cannot be freelychanged. And, the α-cellulose content of the bamboo filament is lowcompared to conventional rayon in which wood pulp or cotton linter isused. For those reasons, in the centrifugal spinning method, thefilament is easy to be affected by the difference of winding tensionsbetween inner and outer layers, to thereby cause difference of dyeingability between winding layers and it becomes necessary to use layersseparately which is inconvenient.

JIS Handbook 32 Paper and Pulp 2004 were referred to regardingmeasurement of the content of α- and β-cellulose, and the content ofother components. In the item g) Property and Test of Pulp Paper andCardboard, of the handbook, the term “α-cellulose” is defined as “Thecomponent which remains without dissolving when pulp or cellulose fiberis treated with 17.5% sodium-hydroxide solution and then diluted to 10%.Note: This content serves as a criteria of judging quality of sample.Refer to JIS P8101 and JIS P90002”. On the other hand, regarding theterm “β-cellulose”, it is described as “The component which reproduceswhen the filtrate of pulp or cellulose fiber is neutralized with aceticacid. Note: Refer to JIS P8010”. Moreover, the Test Method for Pulp forDissolution specified in JIS P 8101-1957 indicated by theabove-mentioned Chemical Fiber Handbook edited by the Society of FiberScience and Technology, Japan was also referred to. In consideration ofthese, as samples, filaments made by the method of viscose process wereevaluated by the methods described in Examples.

In view of good spinnability of bamboo pulp made from bamboo, and inview of processability capable of being used for woven or knitted fabricor nonwoven fabric, and in view of product performance, it is preferablethat the strength/elongation of the filament is 1.5 cN/dtex and 15% byweight or more. To satisfy it, it is preferable that α-cellulose contentis 80% by weight, more preferably, the total content of α-cellulose andβ-cellulose is 90% by weight or more. The α-cellulose contributes to thetoughness of fiber such as strength and elongation and the content ofβ-cellulose and other component of which molecular weight is smallerthan α-cellulose contributes as a component to decrease fibercrystallinity. By increasing the low molecular weight component in arange of fiber performance capable of being made into woven or knittedfabrics, it becomes possible to impart a new property which is differentfrom that obtainable from the filament made by conventional wood pulp.As those new effects, since the low molecular weight component containsan antibacterial component, it decreases crystallinity, excellentcharacteristics in the points of, such as touch, absorption/desorptionproperty, dyeability, negative ions and cool touch, can be obtained.

The filaments made from wood pulp and bamboo pulp, respectively, weredyed in the same bath using direct dye Kayarus supura Blue BWL which isclassified as C (poor level in dyeing uniformity) in the SDCclassification (J. Soc. Dyers. Colourists. 64. 145 (1948)) under thefollowing conditions. The fibers were dipped into the bath at 50° C. andthe bath temperature was raised to 90° C. in 10 minutes. The fibers werewashed with water after 20 minutes. The dye concentration was 0.5% owf,bath ratio was 1:200 and Na₂SO₄ concentration was 10 g/l. Surface dyeingconcentration K/S of the fiber was measured after dyeing. K/S means(1−R)×2/2R, and R means the spectral reflectance at the maximumabsorption wavelength. Measurement of K/S was performed with the D65light source and 10-degree visual field. K/S was 2.69 for the filamentmade from bamboo and 1.81 for the filament made from wood pulp and theresult indicated the structural difference based on the difference ofα-cellulose contents.

The bamboo containing filament yarn may be constituted of either ofmonofilaments or multifilaments. For textiles, the filament may be usedalone or as a composite yarn or as a mixed filament yarn. As for thethickness of the yarn, 10-500 dtex is preferable when used alone, and30-600 dtex is preferable when used as a composite or as a mixedfilament yarn. For a garments application, 450 dtex or less is suitable.In the case of a monofilament, 10 to 50 dtex is preferable, and in caseof a multifilament, it is preferable that single fiber fineness is inthe range of 1 to 20 dtex, since cellulose-based fiber is easy to becomea fluff and it is necessary to secure high processability.

The number of twists needs to be 0 to 3,000 T/M. To make a woven orknitted fabric or a textile having excellent glossy appearance which ischaracteristic to cellulose fiber, 0 T/M (non-twisted) is preferable.Since fluff may be generated at weaving in the case of multifilament. Itis preferable to carry out sizing in such a case. When not performingsizing, it is preferable to choose conditions by adjusting single fiberfineness or total fineness, and additionally imparting low or middletwist of 300 to 1,000 T/M to obtain a required glossy appearance. In theknitting process, since there is less friction than in the weavingprocess, the fiber yarn can be used without twist, but it is preferableto impart a low twist of about 100 to 300 T/M. To impart dry touch,tenseness, resilience and drapability to the woven or knitted fabric, itis preferable that the additional twist number is 1,000 to 3,000 T/M. Ingeneral, cross-section configuration of cellulose-based filament differsaccording its production method. In a viscose or acetate process, it islike a rias type coast and in copper ammonia and organic solventspinning it is generally a round cross section. Although a variantcross-section configuration is possible by the shape of a spinneret, itis preferable to decide the number of twist according to requiredeffectiveness, since the effect of twist differs greatly according tothe cross section configuration. In the case of a cellulose-based fiber,in general, it swells in the presence of alkali or the fiber structurechanges by chemical change. However, since imparting drapability byhydrolysis like in case of polyester is not expected, it is preferableto choose suitably the number of twists and the density of woven orknitted fabric. Moreover, in case of the additional twist number of thecellulose-based filament is in highly twist region of 2,000 to 3,000T/M, in dyeing and finishing process for the woven or knitted fabric,the apparent twist number increases due to the volume expansion in wetcondition. The expansion ratio will be 20 to 30% in the dry state, anddue to the increase of the twist number by the volume expansion andbecause the cellulose fiber is not thermoplastic, a big untwistingstress generates to cause a structural change, and resulted inmanifesting shibo (numerous tiny unevenness). That is, it contributesgreatly to the products which have yoryu georgette crepe or crepe. Inaddition to the dry feeling of the cellulose fiber made from bamboo, atouch by a synergistic effect of twist structure and the unevenstructure is suitable for materials for spring and summer applications.Furthermore, with effects of antibacterial or cold touch, thepossibility of imparting new additional value increases. Moreover, inthe case of the cellulose-based continuous filament yarn made frombamboo or so-called bamboo, although it changes somewhat with processes,as for the point that the stretching behavior of the fiber by a loaddiffers greatly in the presence of water, especially in a damp or wetcondition, it is in the same trend as that of the cellulose-based fibermade from cotton linter or wood pulp. It is preferable to controlhumidity and water content in the process of making woven or knittedfabric or nonwoven fabric.

When the viscose rayon process is utilized as the manufacturing processof the cellulose-based filament, color difference of 1.0 or more as adifference of the dye affinity evaluation E value, ΔE, may occur betweeninner and outer layers of the rolled-up layers in the winding pot andthe quality of the dyed fabric may not be good. In particular, whenmaking it into a composite yarn with other fiber, since it is difficultto classify them and use separately, it is preferable to use thefilament made by the continuous spinning method.

When using the cellulose-based filament as textiles, such as a woven orknitted fabric or a nonwoven fabric, to cover its faults while takingadvantage of its characteristics, it is preferable to use it incombination with other fibers to make a composite. In this case, toexhibit effects of moisture absorption/desorption property,antibacterial property, dry touch, tenseness, resilience, cold touch,and further, generating negative ions, it is preferable to contain 20%by weight or more of the cellulose-based filament, still morepreferably, 30% by weight or more. To impart better antibacterialproperty, moisture absorption/desorption property and cold touch,although it depends on other components used in combination or in thetextile structure, it is also preferable to contain 50% by weight ormore. For example, in the case of imparting moistureabsorption/desorption property, and when regenerated filament is madefrom bamboo made by the viscose process or the cupro ammonium process,it is preferable to make a woven or knitted fabric or nonwoven fabricmade of 100% of such filament, and in such a case, 8-9% as ΔMR of thetextile can be obtained. In the case of blend ratio of thiscellulose-based fiber is changed, absorption/desorption characteristicsis proportional to that blend ratio. If mixed fiber is a polyester type,since the polyester type fiber has almost no moisture absorptionproperty, when the filament is mixed 50% by weight, ΔMR becomes about4-4.5%. Usually, the level felt that moisture absorption/desorptioncharacteristics are comfortable at the time of wear is 2% or more, andit is preferable also from this point, too, that a cellulose-basedfilament is 20% by weight or more in fiber yarn. Theabsorption/desorption property does not depend on how to mix the fibersince it depends on movement of moisture, but as to cold touch feeling,since it is a feeling by directly contacting skin, it depends on thestructure or composite state of the fabric and it is preferable todesign textiles upon confirming data rather than the blending ratio.

As methods for making the composite yarn, conventionally known methodssuch as combination twist in which two or more of said filaments aredoubled and twisted, intersection twist in which said filament isdoubled with other filament or spun yarn and twisted, covering in whichpolyurethane or other spandex yarn is passed through a hollow spindle asa core and the filament is overfed and twisted, filament mixing in whichthe filament is doubled with other fiber and interlaced by compressedair or a composite false twisting by multi-feeding said filament tofalse twister, can be used. However, the cellulose-based filament madefrom bamboo has characteristics of low strength and low shearing stressto become a fluff, and accordingly, it is preferable, especially in caseof multifilament, to be handled carefully under milder conditions thanthose for the conventional synthetic fibers. In particular, it ispreferable, for making a composite yarn by air interlacing, to reduceair pressure very low; for making composite yarn by machines such asdoubling machine, doubling and twisting machine or double twister, tomake curvature of the lot, etc., of the yarn path low, or as straight aspossible; and to reduce the number of guides as much as possible.

The cellulose-based fiber made from a bamboo has antibacterialperformance based on the raw material. The antibacterial component isaffected by chemicals used and heating temperature in productionprocess. In the case of viscose rayon process, the antibacterialproperty is influenced by the heat for increasing α-cellulose contentand removing impurities by treatment with sodium hydroxide or the like.In addition, although the bamboo pulp is made thermoplastic by addingethylene glycol to change it into melt-spinnable thermoplastic polymer,the antibacterial property often decreases by the effect of heat at themelt spinning. For making the system germ activity value of 2.2 or moreso that the antibacterial level passes the SEK standard, it ispreferable to design the yarn in consideration of composite ratio,composite type and its structure. To maintain this natural antibacterialproperty also after washing, it is also preferable to add a chemicalhaving antibacterial effect in dyeing or finishing process. It is alsopreferable to compound the quinine-based antibacterial componentobtainable by ethanol extraction from bamboo or the antibacterialcomponent obtainable by separating from bamboo vinegar liquid which istaken out by compressing bamboo, to the raw material of the fiber, or toprocess it into a textile in dyeing or finishing process. On the otherhand, the antibacterial property may be imparted by compoundingacetylated chitosan which is conventionally used as an antibacterialagent into the spinning liquid, or by processing the obtained yarn orwoven or knitted fabric with the antibacterial agent.

As for the above-mentioned fiber yarn, it is preferable that thecellulose filament and other fiber are made into a composite yarn by amethod selected from doubling and twisting, intersection twisting,covering, filament mixing, false twisting, spinning intersectiontwisting, etc. Although the fiber to be combined is not limited in termsof material or type, it is preferable to choose the material which canexhibit the effect of the cellulose-based filament. For example,although woven or knitted fabric of 100% of cellulose-based fiber yarncan be given a shrink-proofing effect by resin treatment in dyeing orfinishing process, such as with melamine type resin or glyoxal typeresin, the resin treatment may also cause hardening of touch and a badinfluence on the environment by the existence of formalin in the resin.Therefore, to provide shrink-proofing property without resin treatment,making a composite with polyester fiber is also preferable. Moreover,cellulose-based fiber yarn has low wet strength and there is nostretchability in woven or knitted fabric, but by making a compositewith a polyurethane-based spandex fiber or a conjugate fiber usingpolytrimethylene terephthalate-based polymer, or a conjugate fiber of100% polyester-based polymer, it becomes possible to impartstretchability to the cellulose-based fiber yarn and improvement instrength also becomes possible. When considering the environment, it ispreferable to make a composite yarn with the raw material fibers, suchas polylactic acid fiber, cotton, hemp, silk, wool, regenerated fiberwhich uses cotton linter as the raw material.

The cellulose-based filament preferably consists of a biomass resource(non-petroleum resource) for the environment.

The raw yarn to be made into a composite, may be any one of cotton,hemp, wool, silk, spun yarn in which staple fiber of regenerated fiberor semi-synthetic fiber is used, or filament of silk or chemical fiber.It can be a combination in which, as far as the characteristics andeffects of the respective fiber can be exhibited in the woven or knittedfabric or nonwoven fabric obtainable by making the bamboo fibercomposite.

Next, the constitution of the textile using the filament made frombamboo is explained.

As the woven fabric, it may be that in which both of warp and weft areconstituted by the filament or the composite yarn, or may be that inwhich only warp or weft is constituted of the filament. The wovenstructure can be chosen without limitation including publicly knownstructures. Regarding warping, sizing, supra sequence beaming, etc., inthe weaving process, they can be applied in the same conditions asapplied to conventional cellulose-based chemical fiber, for example,rayon yarn, acetate yarn, or Bemberg yarn. In particular, in the sizing,it can be carried out by using a starch-based or a polyvinylalcohol-based paste and by choosing conditions suitably Since shearstrength is low as its characteristic, it is preferable to treat theyarn so that no fluff due to friction is produced. In addition, intensile strength/elongation characteristics (S-S curve) under moistureabsorption or in wet, because the yielding point of stress-straindecreases as humidity increases, the humidity condition of each room ofthe weaving process is set to the standard condition (20° C., 60%) andthe weaving is carried out. Regarding the selection of weaving machine,it is a rapier or an air jet in general, and it is preferable to use awater jet only in the case in which a composite ratio of thecellulose-based fiber is low. In the case of woven fabric in which thefilament yarn is used alone, although basic woven fabrics of such asplain structure, e.g., taffeta, habutae, or three dimensional structure,e.g., twill, satin have wide application for garments such as lining,formal wear, shirts, blouse, or for other materials such as curtains,wrapping cloth and ribbon tape. In addition to that, by making compositewoven fabrics with other natural fibers or chemical fibers, physicalproperties and appearance can be improved and can be applied in wideruses.

Regarding knitting, any of circular knit, weft knit and warp knit can beapplied without limitation. What is necessary is just to use a yarnaccording to the design factor of cloth or fabric corresponding to itsapplication. Like weaving process, it is preferable to set up thecondition so that it does not damage quality by a fluff and yarnbreakage caused by the strength/elongation characteristics and shearstress characteristics in dry and wet conditions.

In the manufacturing method of a nonwoven fabric, although suitableconditions can be chosen according to the fiber used, most preferablemethod is span bond method, and it can be made into cloth by needlepunching or water punch interlacing to the web.

Regarding dyeing, it can be carried out according to the procedure forconventional cellulose-based fiber such as rayon, Bemberg or acetate.The performances in dyeing process such as swelling and decrease ofstrength in the existence of alkali are almost the same as those of theconventional cellulose-based fiber, and dyeing method, selection ofmachine and other condition, etc., can be tried and decided, ifnecessary.

EXAMPLE

Hereafter, our yarns are explained with reference to Examples. However,the description is not limited to these examples.

<Evaluation Method>

Measurement of the α-cellulose content, β-cellulose content, content ofa low molecular weight component and others was performed by thefollowing method. Measurements relating to weight change depending onmoisture absorption were carried out in the standard room conditioned to20° C., 65%. Other treatment such as heating was carried out in anordinary chemical laboratory. Average value of two samples was used.

(1) Defatting of Fiber

Using ethanol benzene mixed liquid (mixing ratio 1:1), Soxhlet'sextraction of 4 hours was performed.

(2) Separation of α-Cellulose

About 1 g of absolutely dried fiber is immersed in aqueous solution of17.5% sodium hydroxide (bath ratio: 1:100) for 2 hours at roomtemperature. The content is filtered by a glass filter, washed withwater, neutralized with acetic acid and then weighed after absolutedrying. 150 mm of “ADVANTEC2” (made by TOYOROSHI KAISHA LIMITED) is usedfor the filter paper.

(3) Separation of β-Cellulose

The filtrate at the time of α-cellulose separation and the washingliquid before neutralization are collectively set to 800 mL, and 40 mLof 30% acetic-acid solution in water is added to this, and it is heatedslowly (the beaker containing the solution is put into another containerinto which the boiling water was put to heat it indirectly). The beakerafter heating is taken out and β-cellulose is made to reproduce andcondense. About 2 hours after the liquid becomes transparent, it isfiltered through a filter paper, washed with water, absolutely dried andweighed.

(4) Other Components

It is determined by subtracting α- and β-cellulose from the originalfiber weight.

The quality evaluation in the examples was performed by the followingmethod.

[Hygroscopicity (ΔMR)]ΔMR (%)=MR ₂ −MR ₁

Here, MR₁ denotes the moisture absorption (%) when leaving it for 24hours from an absolute dry condition to the atmosphere of 20° C.×65% RH,and it is the condition in wardrobe, i.e., namely equivalent to thecondition before wear. On the other hand, MR₂ denotes the moistureabsorption (%) when leaving it for 24 hours from an absolute drycondition to the atmosphere of 30° C.×90% RH, and it is almostequivalent to the condition in the clothes in an exercise.

ΔMR is expressed with the value which subtracted the value of MR₁ fromMR₂ and it is equivalent to how much moisture in clothes can be absorbedwhen it is put on during exercise. It can be said that it is morecomfortable as the ΔMR value increases. Generally, it is said that ΔMRvalue for polyester is 0%, for nylon, 2%, for cotton 4% and for wool 6%.

[Antibacterial Property]

The standardized test method was used for the evaluation method, and asthe test fungus, clinical isolate of yellow staphylococcus aureus wasused. In the test method, the above-mentioned test fungus is poured intosterilization test cloth, measured the number of the fungus after18-hour culture, determined the number of the fungus over the initialnumber of the fungus, and followed the following criteria.

In the condition of log(B/A)>1.5, log(B/C) was made into thebacteriostasis activity value, and 2.2 or more were considered assuccess. Here, A1 denotes number of fungus of unprocessed articlecollected just after inoculation, B1 denotes number of fungus of theunprocessed article after 18 hours culture, C1 denotes number of fungusof the processed article after 18 hours culture.

[Number of Generated Ion]

Measuring device: AIR ION COUNTER IC-1000 (made by Alpha LAB (U.S.))

Measuring condition: room temperature of 20±1° C., humidity of 50±3%,room size 3 m×5 m×5 m

Measuring-time 10 seconds, suction volume 12 L/min and sample vibrationcycle 3 cycles/second

Sample size 30 cm×20 cm

Evaluation result: average number of generated ion in 10 seconds afterstart of measurement (piece/cm³)

It is indicated in a negative value when a negative ion is generated anda positive value when a positive ion is generated. The total of thenegative and positive values is considered as the number of generatednegative ions. −1000 pieces/cm³ is considered as success.

Example 1 and Comparative Examples 1, 2

A repulped raw material with a high content of α-cellulose component wasprepared by making a pulp from a bamboo of China, and further refiningthe pulp by immersing it in caustic soda, and then mashing and refining.Using the repulped raw material, a multi-filament yarn of 130 dtex-30rayon filament was spun by centrifugal spinning to thereby prepare acake of 525 g in weight. As comparisons, a multi-filament yarn of 120dtex-30 made from cotton linter pulp and made by centrifugal spinningand a multi-filament yarn of 84 dtex-24 made by the continuous spinningprocess were prepared. The obtained filament yarns of the centrifugalspinning, the refined cake, and the cheese made by the continuousspinning were inspected. Although it was practically equal concerningsurface irregularity when the filament yarn made from cotton linter pulpand the filament yarn made from bamboo pulp were compared, but as aresult of observing the cross sections, the filament made from bamboohas slightly flat cross section and its white color was a little bityellowish. The result of the physical properties measured is shown inTable 1.

The strength of the multi-filament yarn made from bamboo was low ascompared with that of the filament yarn of the centrifugal spinning madefrom a cotton linter, and was almost comparable as that of the filamentyarn of the continuous spinning. Elongation was a little bit larger thanthat of the centrifugal spinning and the boiling water contraction wascomparable with that of the centrifugal spinning. In the colorimetry ofthe yarn color, lightness was practically equal, although the filamentmade from bamboo was rich in yellow tone and the filament made fromcotton linter was rich in blue tone. The obtained two multifilamentyarns of continuously spun and taken into cakes made from bamboo andcotton linter were served for woven fabric preparations.

The test conditions are as follows.

The warp was subjected to middle twist of 1,000 T/M by a double twister,to vacuum steam twist set at 70° C. for 30 minutes, to partial warpingand supra sequence, and woven by a rapier loom in 3/3 twill constructionusing various wefts. The obtained gray fabrics were passed to dyeing andfinishing process. To observe wet behavior of the fabric in the dyeingprocess, scouring and relaxation were carried out by changing M/C modelpartially. The relaxation temperature was 98° C. in all cases. In thecase of weft having additional twist, the fabric made of the yarn ofExample 1 which was subjected to liquid flow relaxation, showed a largeswelling in volume and a large processing contraction. The feeling ofthe fabric just after relaxation was very dry which is different fromconventional rayon yarn, namely, it was a dry touch like that of anacetate. Moreover, the crimp due to structural contraction of the warpand the weft caused by the swelling was notable, and the fabric was veryexcellent in tenseness and resilience. It is presumed that this isbrought about by the fact that, although the multifilament yarn madefrom bamboo was prepared in the same centrifugal spinning condition asthat of the multifilament yarn made from cotton linter, as seen from thedifference of characteristics in tensile strength and tensileelongation, the α-cellulose content of bamboo is lower than that ofcotton linter and there is a difference in molecular orientation tobring about high swelling in water.

The fabrics of the test Nos. 1, 2 and the comparative one after theliquid flow relaxation, were dyed with a reactive dye, and the finishedfabrics were sewed into a bottom (pants) for lady. Compared to thecomparative one, No. 1 showed a dry touch and had a tenseness and anatural stretchability of 8 to 10% due to the yarn contraction byswelling. And the appearance of the sewed article was good. On the otherhand, No. 2 had a stretchability in weft direction of about 20% and ithad a dry touch more elegant than No. 1, and the sewed article had goodappearance with an excellent silhouette.

The gray fabrics and their process parameters are shown in Table 2.

Examples 2 to 10 and Comparative Example 3

Using 84 dtex×24 filament bright filament yarn made from bamboo pulpmade by the centrifugal spinning method of viscose rayon process and,for comparison, a rayon bright filament yarn made from wood pulp (84dtex×24 filament), various textiles were prepared. The contents ofα-cellulose, β-cellulose and other components of both rayon filamentswere determined by the above-mentioned chemical analysis. As a result,the component ratio contained of the filament made from bamboo wasα-cellulose 87.5% by weight, β-cellulose 10.6% by weight and othercomponents 1.9% by weight. On the other hand, as for the filament madefrom wood, it was α-cellulose 90.8% by weight, β-cellulose 9.0% byweight and other components 0.2% by weight.

Examples 2 and 3, used 84 dtex-24 filament made from bamboo as warp and,without combining with other yarn and without additionally twisting,subjected to sizing and warping and set to a rapier loom. A fabric inwhich, as weft, (A) the yarn used in the warp (Example 2) is used, and afabric in which, as weft, (B) a composite yarn, in which a crimpedconjugate fiber yarn (56 dtex-24 filament) made by a bimetal typecomposite spinning of PET/PPT (polyethyleneterephthalate/polytrimethylene terephthalate) was doubled with the yarnused in the warp and intersection twisted, was used (plain habutae andtwill habutae, Example 3), were made and subjected to dyeing andfinishing.

In the case of a woven fabric of conventional rayon filament yarn inwhich the warp is not additionally twisted, a slimy touch is its generalimage, but the fabric made of the filament made from bamboo has a slimytouch which is relatively dry, and was a woven fabric of a novelfeeling. The woven fabric was sewed into a shirt. An article with a highquality feeling having a fresh dry touch was obtained.

In Examples 4 and 5, as warps, filament made from bamboo (84 dtex-24filament) additionally twisted in S and Z directions, respectively, werewarped alternatively and wound on a warp beam and set to a loom. Afabric in which, as weft, (A) the highly twisted yarn used as the warpis used, and a fabric in which, as weft, (B) a composite yarns, in whicha crimped conjugate fiber yarn (56 dtex-24 filament) made by a bimetaltype composite spinning of PET/PPT was doubled with the yarn used as thewarp and twisted in S and Z directions, respectively, in the twistnumber of 1,500 T/M by a double-twister and each two of them was usedalternatively to thereby obtain union clothes (plain georgette and crepegeorgette) and the clothes subjected to dyeing and finishing.

Dyeing and finishing was carried out to the fabric (example 4) of theusual plane finishing, and to the fabric (example 5) with the surfacechange by tumbler drying.

In the tumbler dried fabrics, the fabric in which PET/PPT crimpedconjugate yarn was used as the weft showed an excellent surface change,and had dry and light touch with excellent stretchability. Regarding thefeeling of the finished fabrics, both of them had relatively dry touchwith excellent stretchability, tenseness and resilience, which isdifferent from the feeling of conventional rayon woven fabric. As theresult of sewing them into dresses, articles excellent in drapabilityand appearance were obtained.

Example 11

The test yarn of Example 1, 120 dtex-30 filament yarn made from bamboowas used as weft, and a beam of a regular polyester filament (56T-36filament) of triangular cross sectioned bright yarn having a low twistof 200 T/M and sized, was set to a air jet loom as warp. The cake of thetest yarn was rewound by a cone winder for filament and additionallytwisted in S and Z directions in the twist number of 1,300. A plainweave was made by alternatively filling the S and Z additionally twistedyarns. In the gray fabric, the woven density was 167 warp yarns/2.5 cmand 82 weft yarns/2.5 cm. Next, as a dyeing process, the fabric wassubjected to scouring and relaxation at a condition of 50 to 98° C. byan open cloth type scouring and relaxation machine, the open soaper, andafter pre-set by dry heat tenter at 180° C., 15% weight reduction ofpolyester by alkali in wince type M/C with caustic soda with anamine-based reduction accelerator was carried out, and, by a liquid flowdyeing M/C, dyed only the cellulose side in very light color with areactive dye. The densities of the warp and weft of the obtained fabricwere 176×97 yarns/2.5 cm, respectively. As a result of evaluation of thefinished fabric, in warp and weft directions, dimensional contraction by180° C. dry heat was −0.5% and −1.5% respectively, tear strength was1,359 g and 750 g, respectively, seam displacement was 0.8 mm and 0.5mm, respectively, snagging was grade 4 and grade 4, respectively,pilling according to JIS 1076 method (ART method, the method byappearance retention type tester) was grade 4 to 5. All of these arequalities which can pass the application standard for linings of juban(underwear of kimono), susoyoke (a lining of kimono), etc. Moreover,ΔMR, a barometer of feeling at the time of wear, was 5.2, contrary toregular polyester which absorbs almost no moisture, and the touch of thetest fabric had cold feeling which may be due to the moisture absorptioneffect, and has a light and dry touch. Compared to the touch of theconventional rayon which is slimy, the touch of this test fabric wassomewhat similar to that of acetate rather than to that of rayon, and itwas different from that of viscose type. The result of measurement ofnegative ions showed that the number of negative ions was 6000 ions/ccand the number of plus ion was 1,000 ions/cc.

Example 12 and Comparative Example 4

Using the test yarn of Example 1, 120 dtex-30 filament, a woven fabricby pre-dyed yarn was prepared. The test yarn, after an additionaltwisting of 200 T/M, wound on a soft wide cheese and subjected to acheese dyeing with a reactive dye. As the warp, a polyester dyed yarn ofsemi-dull 56T-24 filament of round cross section was warped and the dyedyarn was filled as the weft by an air-jet loom and a plain weave withcheck design of beige, red and black was made. In the dyeing process,the plain weave was subjected to scouring, relaxation, set, drying,treatment of a finishing agent and final set to thereby make a wovenfabric for lining application. The quality feeling of the fabric was,being different from that of polyester 100%, light and dry with a coldfeeling. Compared to a lining of the almost same design in which aBemberg filament is used, unlike the Bemberg lining which is veryslippery and a little bit slimy, the fabric of this test had a touchexcellent in fresh feeling.

Regarding absorption/desorption property, it was excellent as Δ6.3%, thefrictional electrification voltage was 0 which indicates an excellentantistaticity.

Example 13

The test filament 130T-30F of Example 1 was set to a creel of a warpingmachine, and wound on a beam of 30 cm width and set to a tricot machine.A mesh construction was knitted with total warp of 4,212 yarns and frontand back reeds with the test filament having no twist. The width of thegray fabric was 254 cm, well 28 W/25 cm, course 41 W/25 cm, 150 racks,weight 14.2 kg. Next, the fabric was passed to a dyeing processes. Theprocesses were constituted by set of the gray fabric, dyeing, drying,resin processing, final set and the finished fabric had structuralparameters of 247 cm width, well 28 W/2.5 cm, course 42 W/2.5 cm. Thefinished fabric had a dry and fresh cold feeling and suitable forlinings of summer wares.

Example 14 and Comparative Example 5

A pulp made from bamboo was refined again, and a viscose spinningsolution was prepared by the process for making viscose rayon from woodpulp or cotton linter, and a bright yarn of 84 dtex×24 filament was madeby, as the spinning method, centrifugal spinning (cake winding) and bycontinuous spinning method (cheese winding). The cake was scoured in thefollowing process and rewound on a cone by a rewinder. The weight ofsingle cake was set to 550 g and the weight of single cheese ofcontinuous spinning was set to 1 kg. The quality of the raw yarn forwoven or knitted fabric needs uniformity. In the case of a viscoseprocess filament made from bamboo, compared to conventional raw yarnmade from wood pulp, there is an inclination that the content ofα-cellulose component is low and the content of β-cellulose and otherlow molecular weight component is high. That is, because itscrystallinity is low and the content of amorphous portion is high tocheck whether there is no problem in level dyeing, concerning thedifference of inner and outer layers of package or the differencebetween spinning machines, respective yarns were continuously filled asweft, and then the gray fabric was dyed in a same batch. Dyeing andfinishing were carried out by a high pressure liquid flow dyeing machinein one bath two step dyeing with a disperse dye 0.3% owf and a directdye 0.15% owf (both were blue), the bath ratio 1:10 and the dyeingtemperature 130 to 90° C. After final set, by checking the fabric byvisual inspection and by the difference of E value, ΔE*a*b*, accordingto L*a*b* color-coordinate-system measurement by spectral colorimeter,the difference between inner and outer layers of cake, the difference ofinner and outer layers between cakes (spinning machines), the differencebetween inner and outer layers of the cheeses of continuous spinning anddifference of inner and outer layers between cheeses (spindles) weremeasured and compared. The colorimetry is carried out by spectralcolorimeter CM-3600 of MINORUTAKONIKA Sensing Co. Ltd. and with lightsource D65.

As a result of the colorimetry, every cake yarn exhibited dyed colordifference, ΔE, far larger than the acceptable value, 0.5, whichdifference was a level capable of realizing by visual inspection of thefabric, and it was necessary to use separately, as warp, the inner andouter layers. On the other hand, the ΔE value of the continuous spinningyarn of between inner and outer layers of cheese and the differencebetween cheeses were in the range of 0.5 or less, and it was confirmedthat it is a quality which could be reliably used.

Example 15

Using a bright yarn of 84 dtex-24 filament made from bamboo and made bycontinuous spinning of viscose process of Example 14, and a doubled andtwisted yarn of a bright yarn of 84 dtex-36 filament of polylactic acidfiber filament with a number of twist of 1,000 T/M in S direction, asthe warp and the weft, respectively, and a woven fabric of plainconstruction was made by a rapier loom. Dyeing and finishing werecarried out according to the general conditions for ordinary viscoserayon woven fabric except the condition for imparting natural wrinkle tothe fabric beforehand. Dyeing was carried out with a disperse dye at110° C. and with a reactive dye at 80° C. The fabric obtained wasfinished so that no iron is necessary in view of the iron-proof propertyof the polylactic acid fiber. The appearance matched the quality feelingof cellulose-based fiber made from bamboo, with a natural feeling andvery dry touch, and a fabric having a quality feeling capable ofapplying to summer wares was obtained. The fabric is expected, from theecological combination, as a material which is effective to preventenvironmental pollution in the future, because it is constituted ofcellulose-based fiber made from bamboo and the polylactic acid fibermade from corn, and combustion energy and the CO₂ generation can bedecreased. In addition, as a result of measurement ofabsorption/desorption property, ΔMR was 4.5 which means that 50% use ofthe cellulose-based fiber corresponds to the effect of cotton, thus, itis a material suitable for spring/summer wares.

Example 16

Using a part of the cake yarn of viscose process filament made of bambooand continuous spinning yarn used in Example 14, composite yarns, by acomposite false twisting process with different feeding speeds, with athick-and-thin yarn of semi-dull type polyester filament of 84 dtex-36filament were prepared. The composite false twisting process wasconducted according to the publicly known method disclosed inJP-B-59-26989, “A false twisted composite highly twisted yarn and amethod making thereof”. As the false twisting machine with two feedingportions, spindle type false twister 103 made by Toshiba Machine Co.,Ltd. with first and second heaters was used. The conditions were set to,false twisting spindle rotation speed, 110,000 rpm; number of falsetwisting, 2,570 T/M; over-feed ratio of covering yarn to core yarn, 90%;first and second heater temperatures, 175° C. and 185° C., respectively.As the feed yarns, for the core yarn of the composite false twistedyarn, the polyester thick-and-thin yarn was used, and for the sheathyarn which constitutes a slub yarn having singly folded portions andtriply folded portions, the cellulose-based filament made from bamboowas used. Process conditions suitable for the cake yarn and thecontinuous spinning yarn in the false twisting process was tested. Itwas found that the factor which is most important to improveprocessability and configuration stability of the yarn, namely thecondition for the sheath yarn to entangle to the core yarn firmly whenoverfed and make it possible to maintain its configuration when used aswarp in weaving stage is that it is necessary to additionally twist thesheath yarn. It was also found that the number of additional twistsshould be larger for the continuous spinning yarn than for the cakeyarn. The number of the additional twist for the cake yarn was 200 T/Mand for the continuous spinning yarn was 350 T/M. It is believed that,at entangling to the core yarn, the multifilament yarn of continuousspinning lacks unity. At spinning of the cake yarn, an original twist isimparted to the filament yarn by rotation of pot when wound.

The obtained two types of the composite false twisted yarn were used aswarp and weft, respectively, and a plain woven fabric and a twill wovenfabric were prepared and dyed and finished. The woven fabrics obtainedwere sewed into a gauze-like and haori type spring/summer jacket. As aresult, the filament yarn made from bamboo constitutes most of thesurface of the fabric and it was a fabric having a high quality feelingof dry touch and a good surface appearance. The absorption/desorptionproperties, ΔMR, of both of the fabrics, were level 7, which is farlarger than 4% of cotton, and it was recognizable at the time of wear.In addition, regarding antibacterial property, although it cannot beachieved entirely by conventional rayon product due to also theinfluence of false twisting, it was 1.7 in the fabric, according to theunited evaluation method of SEK. Although 1.7 was under the passablelevel, by MAKSPEC process to impart an antibacterial component at dyeingwhich is a processing technology of Toray Industries at dyeing andfinishing process, the fabric could clear the SEK standard, 2.2 or more,after 20 times washing.

TABLE 1 Example 1 Comparative example Test yarn 135 dtex-30F 1 2(centrifugal spinning) Yarn for comparison 120 dtex-30F Yarn forcomparison Middle Inner (same as left) (continuous spinning) Outer layerlayer layer Outer layer Middle layer Inner layer — Apparent yarnthickness (dtex) 137.4 140.3 141.3 129.0 130.8 132.9 83.9 TensileStrength (cN) 209.8 212.1 210.8 264.4 261.4 262.1 136.3 Elongation (%)21.4 25.3 25.7 18.7 20.6 20.6 20.8 Boiling water contraction (%) 0.7 0.00.0 1.5 0.8 0.3 5.2 Dry heat 120° (%) 0.4 0.4 0.3 0.4 0.3 0.3 0.9contraction 160° C. 0.6 0.7 0.6 0.5 0.5 0.3 0.9 180° C. 0.8 0.9 0.7 0.40.5 0.5 0.9 Colorimetry L value 88.52 87.74 87.80 89.69 89.77 89.77 — avalue −3.78 −4.12 −4.05 −9.36 −9.19 −8.18 — b value 8.05 8.16 8.48 0.360.65 0.76 — * Measurements are based on JIS L1013 “Chemical fiberfilament yarn test method” * However, colorimetry is conducted bydensely distributed filament yarn on a flat aluminum plate, and L(lightness), a value (+ reddish, − bluish) and b value (+ yellowish, −bluish) were determined.

TABLE 2 Example 1 1 2 3 4 5 Co. example 1 Warp Yarn used 130 dtex-30F120 dtex-30F Number of additional twist (T/M) 1,000 Weft Yarn used sameas warp PTT/PEP cotton yarn same as warp conjugate 60/2 56T-24/2 Numberof additional twist (T/M) 1,000 — 0 1,000 Gray fabric Width (cm) ×Length (m) 133 × 52 129 × 52 131 × 52 147 × 136 143 × 127 141 × 12  Warp× Weft densities (yarns/2.5 cm) 157 × 88 162 × 90 160 × 78 196 × 100 200× 94  204 × 110 Construction 3/3 twill 3/3 twill 3/3 twill 3/3 twill 3/3twill 3/3 twill Relaxation Liquid flow Width (cm) 115 89 123 125 95 120method Width contraction (%) 13.5 31.0 6.5 14.9 32.8 14.8 Yarn density(%) 108 116 85 110 114 120 Length contraction 22.7 28.8 8.9 10.0 21.21.1 Touch dry dry & dry & soft dry dry a little slimy stretchable Opencloth Width (cm) 122 95 122 — — — method Width contraction (%) 8.3 26.36.8 — — — Yarn density (%) 103 107 80 — — — Length contraction 17.0 18.81.0 — — — Touch dry/light dry/light & dry/light & — — — stretchable soft

TABLE 3 Example 2 Example 3 Example 4 Example 5 A B A B A B A B WarpCellulose-based fiber used 84T-24F Bright (rayon filament by centrifugalspinning) made from bamboo Yarn combined — Combination method — Totalthickness (dtex) — Cellulose-based fiber content 100 Number ofadditional twist (T/M) O (sizing) S 1,500 Weft Cellulose-based fiberused 84T-24F Bright (rayon filament by centrifugal spinning) made frombamboo Yarn combined — 56T-24F*1 — 56T-24F*1 — 56T-24F*1 — 56T-24F*1Combination method — D/IT, C — D/IT, C — D/IT, C — D/IT, C Totalthickness (dtex) — 140 — 140 — — Cellulose-based fiber content 100 60100 60 100 140 100 140 Number of additional twist (T/M) 0 1,000 0 1,000S, Z 0 S, Z 1,500 0 1,500 S, Z 1,500 S, Z 1,500 Gray fabric Contractionin labo. Length 17.0 23.3 14.2 22.0 — — — — (boil × 30 min.) Width 5.111.8 5.3 11.1 — — — — Width (cm) × Length (m) 129.5 132.4 131.5 132.0131.0 125.0 131.0 125.0 Woven density (yarns/2.5 cm) 77 64 96 87 99 10482 95 Woven construction plain (habutae) twill (habutae) plain (chiffoncrepe (crepe georgette) georgette) Dyeing Relaxation Width (cm) 122.0105.2 122.5 106.5 — — — — Weft density (yarns) 93 83 118 118 — — — —Dyeing/finishing Width (cm) 116.0 98.5 114.0 100.0 94.5 84.3 94.0 76.5Weft density (yarns) 93 83 76 80 80 90 93 99 Touch Dry touch Very goodTenseness, resilience Good Very good Drapability Good Very goodStretchability Good Very good Good Very good Coloration Good averageGood Very good Physical Dimensional change by Length −10.9 −4.8 −7.0−4.8 −5.6 −4.2 1.1 −4.6 properties washing Width 0.8 −0.3 0.1 −0.3 0.20.4 4.3 0.3 (JIS L1096) (F-1 or G method) Tear strength (N) Length 7.220.8 14.6 20.8 13.5 14.7 17.3 20.3 (Pendulum method. Width 4.7 14.0 7.014.0 6.8 7.0 10.7 10.2 Stretch (%) Length — (1.5 kg · f) Width — 6.5 —7.8 23.0 29.5 25.5 40.5 Note) *1: Multifilament yarn of polyethyleneterephthalate 50/polymethylene terephthalate 50 side by side typeconjugate fiber *2: “D/IT, C” denotes “Doubling/intersection twist andCombined weave”.

TABLE 4 Comparative Example 6 Example 7 Example 8 Example 9 Example 10example 3 Warp Cellulose-based fiber used 84T-24F Bright (rayon filamentby centrifugal spinning) made from bamboo 84T-24F Bright (regular rayonfilament by centrifugal spinning) made from wood pulp Yarn combined — PU44*3 — PET 33T-12F — Combination method Doubling and W covering DoublingFilament mixing + Doubling and twisting and twisting additional twistingtwisting Total thickness (dtex) 168 182 168 117 168 Cellulose-basedfiber content 100 92 100 72 100 Number of additional twist S, Z 1,200 S,Z 800 S 1,000 S 800 (T/M) Weft Cellulose-based fiber used 84T-24F Bright(rayon filament by centrifugal spinning) made from bamboo Yarn combinedPU 44*3 56T-24F/2*1 Combination method Single Same as warp/combinedDoubling and twisting/combined weave covering/combined weave weave Totalthickness (dtex) 182 112 Cellulose-based fiber content 92.3 0 Number ofadditional twist S 800 S 1000 (T/M) Gray fabric Contraction in labo.Length 12.1 40.5 40.0 10.9 13.4 6.5 (boil × 30 min.) Width 36.5 33.636.3 13.1 20.0 8.3 Width (cm) × Length (m) 191 × 29.7 177 × 57.0 180.0 ×57.0 144.7 × 27.0 144.5 × 25.9 144.0 × 26.0 Warp × weft density 84 65 8796 89 95 (yarns/2.5 cm) Woven construction venetian tromat 2/2 twill 3/2twill Dyeing Relaxation Width 120.0 108.0 107.5 119.0 103.5 121.0 (cm)Weft 94 89 120 109 100 105 density (yarns) Dyeing/finishing Width 126.5106.0 105.6 112.0 106.0 116 (cm) Weft 101 91 113 116 110 110 density(yarns) Touch Dry touch Very good Good Very good Good Tenseness,resilience Good Very good Good Drapability Good average Very good GoodStretchability Very good Good Average Coloration Good Very good GoodVery good Physical Dimensional change Length −0.6 −5.4 −5.5 −0.8 −0.6−1.2 properties by washing Width 1.2 0.4 −0.6 0.5 0.9 1.1 (JIS L1096)(F-1 or G method) Tear strength (N) Length 31.4 29.8 28.2 31.4 31.4 32.5(Pendulum method. Width 11.1 23.4 26.3 27.4 17.6 29.0 Stretch (%) Length9.0 35.3 41.3 10.3 — 5.2 (1.5 kg · f) Width 39.5 56.5 56.0 10.3 14.5 4.5(Note) *3: As PU 44T, “Lycra T 127C” made by Opelontex Co., Ltd. wasused in draft ratio of 3.0.

TABLE 5 Yarn to be evaluated Continuous spinning yarn made Cake yarnmade from bamboo from bamboo Dyeing difference Dyeing difference Dyeingdifference Dyeing difference Sample No in cake between cakes in cheesebetween cheeses 1 Inner layer 1.46 out/out 1.4 0.5 out/out 0.21 Outerlayer in/in 1.16 in/in 0.21 2 Inner layer 0.86 0.41 Outer layer 3 Innerlayer 0.81 out/out 0.75 0.45 out/out 0.35 Outer layer in/in 0.61 in/in0.5 4 Inner layer 0.31 0.17 Outer layer 5 Inner layer 1.14 out/out 0.740.37 out/out 0.25 Outer layer in/in 1.59 in/in 0.08 6 Inner layer 1.320.05 Outer layer 7 Inner layer 1.13 out/out 1.11 0.38 out/out 0.16 Outerlayer in/in 1.47 in/in 0.45 8 Inner layer 0.97 0.38 Outer layer 9 Innerlayer 1.35 out/out 1.37 0.19 out/out 0.32 Outer layer in/in 0.58 in/in0.32 10 Inner layer 1.0 0.21 Outer layer 11 Inner layer 1.12 0.40 Outerlayer Note: Warp: 56 dtex-36 filament round cross section bright yarn ofregular polyester Weft: 1) Bright yarn of 84 dtex-24 filament made frombamboo made by viscose process centrifugal spinning 2) Bright yarn of 84dtex-24 filament made from bamboo made by continuous spinning Weaving:The cake (wound weight 550 g) for the weft 1) was rewound on cones asweft. 11 cones (cake) were continuously filled by air jet loom in oneunit. 11 cheeses (wound weight 1 kg) for the weft 2) were continuouslyfilled. Weaving construction was plain (taffeta). Dyeing: The standardprocess of taffeta for lining was carried out (open clothscouring/relaxation - dry heat pre-set - beam dyeing - final set). Areactive dye (%) was used.

1. A fiber yarn which is a yarn containing a bamboo pulp filament havingabout 80 wt % to about 87.5 wt % of an α-cellulose component and havinga thickness of about 10 to about 600 dtex and number of twist of 0 toabout 3,000 T/M.
 2. The fiber yarn according to claim 1, wherein thefilament is 85 wt % to 87.5% wt % of α-cellulose component.
 3. The fiberyarn according to claim 1, wherein a total amount of α- and β-cellulosecomponent in said filament is about 90 wt % or more.
 4. The fiber yarnaccording to claim 1, wherein the filament is produced by a continuousspinning system of viscose rayon process.
 5. The fiber yarn according toclaim 1, wherein the fiber yarn contains at least about 20 wt % of saidfilament and another fiber that is at least one fiber selected from thegroup consisting of natural fiber, regenerated fiber, semi-syntheticfiber and synthetic fiber.
 6. The fiber yarn according to claim 5,wherein the filament and the another fiber are made into a composite byany one method selected from the group consisting of doubling andtwisting, covering, filament mixing, false twisting and spinningintersection twist.
 7. A cloth comprising a woven or knitted fabric or anon-woven fabric comprising the fiber yarn according to claim
 1. 8. Thefiber yarn according to claim 1, wherein the filament is 87 wt % or moreof α-cellulose component.